This invention relates generally to improvements in devices and systems for chilling a selected beverage such as water or the like. More particularly, this invention relates to improvements in a beverage or water cooler of the type equipped with a compact thermoelectric heat transfer module for quietly and efficiently chilling the liquid contained within a cooler reservoir.
Water coolers are well known in the art for containing a supply of a selected beverage such as relatively purified water in a convenient manner and location ready for substantially immediate dispensing and use. Such water coolers commonly include an upwardly open reservoir adapted to receive and support a water bottle of typically three to five gallon capacity in an inverted orientation such that bottled water may flow downwardly into the cooler reservoir. A faucet or spigot on the front of a cooler housing is operable at any time for on-demand dispensing of the water in selected amounts. Such bottled water coolers are widely used to provide a clean and safe source of drinking water, especially in areas wherein the local water supply may or is suspected to contain undesired levels of contaminants. In one alternative configuration, the upper end of the cooler reservoir is normally closed by a lid which can be opened as needed for periodically replenishing the reservoir water by pour-in addition of water thereto. In other known alternative water cooler designs, the cooler reservoir is replenished by connection to a water supply line, and may include water filtration and/or purification means such as a reverse osmosis unit for purifying water supplied to the cooler reservoir.
In many water coolers of the type described above, it is desirable to chill or refrigerate the water or other beverage within the cooler reservoir to a relatively low, refreshing temperature. However, refrigeration equipment for such water coolers has typically comprised conventional compressor-type mechanical refrigeration systems which undesirably increase the overall cost, complexity, size, operational noise level, and power consumption requirements of the water cooler. Alternative cooling system proposals have suggested the use of relatively compact and quiet thermoelectric heat transfer modules, such as the systems shown and described in U.S. Pat. Nos. 5,072,590; 6,003,318; and 6,119,462. In such proposals, a thermoelectric module is mounted with a cold side thereof disposed in heat transfer relation with water in the cooler reservoir, and a hot side associated with a heat sink for dissipating heat drawn from the water. A cooling fan is normally provided to circulate air over the heat sink for improved heat transfer efficiency.
In such thermoelectric chiller systems, the thermoelectric heat transfer module is normally sandwiched in clamped relation between a chiller probe or other cold surface structure disposed in heat transfer relation with the beverage or water to be chilled, and a fin-type heat sink for dissipating the collected heat energy. However, during normal operation, the heat transfer module is exposed to significant thermal cycling with resultant expansion and contraction which can reduce the clamping force applied thereto and correspondingly reduce the thermal coupling efficiency with respect to the chiller probe and heat sink.
The present invention provides an improved thermoelectric beverage cooler including an improved mounting arrangement for supporting a thermoelectric heat transfer module with substantially uniform pressure distribution between a chiller probe and a heat sink.
In accordance with the invention, a beverage cooler is provided with an improved thermoelectric chiller unit for chilling a supply of water or other selected beverage within a cooler reservoir. The improved thermoelectric chiller unit includes a thermoelectric heat transfer module captured by a spring mount with substantially uniform pressure distribution between a chiller probe for chilling the water within the cooler reservoir, and a heat exchanger or heat sink for dissipating heat drawn from the chilled water.
In the preferred form, the thermoelectric heat transfer module comprises a solid state chip having semiconductor materials with dissimilar characteristics (P-type and N-type materials) connected electrically in series and thermally in parallel, such as the heat transfer module available from Borg-Warner Corporation under model designation 920-31. This heat transfer module is sandwiched between a chiller probe and a heat sink, both formed from a selected material having relatively high thermal conductivity, such as aluminum or the like. Fasteners such as a pair of screws are provided to interconnect the chiller probe and heat sink, with the thermoelectric heat transfer module sandwiched in clamped relation therebetween. In accordance with one aspect of the invention, the fasteners are passed through the opposite ends of an elongated spring strip having a central resilient spring segment extending toward and bearing against one of the clamping structures, such as the heat sink in the preferred form of the invention. This spring strip uniformly maintains the components in tightly clamped relation, while substantially uniformly distributing the clamping forces across the surface area of the thermoelectric heat transfer module to reduce or eliminate undesirable module cracking during use.
In accordance with other aspects of the invention, the cooler reservoir has an inverted and generally cup-shaped receptacle formed in a bottom wall thereof for close slide-fit reception of the chiller probe when the reservoir is installed into a cooler housing. An upwardly open insulation shell is provided within the cooler housing for nested reception of the cooler reservoir to insulate the reservoir contents. A faucet is mounted on a front side of the reservoir for use in dispensing the reservoir contents, wherein this faucet is exposed for access at a front side of a cooler housing through aligned gaps formed in the cooler housing and the insulation shell. The reservoir with faucet thereon is removable as a unit from the cooler housing.
Other features and advantages of the invention will become more apparent from the following detailed description, taken in conjunction with the accompanying drawings which illustrate, by way of example, the principles of the invention.